Balance relay



W. H. PETERSEN BALANCE RELAY Jan. l0, 1950 Filed June 22, 1945 .I 1N" VEN TOR. l/z/Mg/m /1 /QQ//EQU Patented Jan. 10, 1950 UNITED STATES PATENT OFFICE BALANCE RELAY Application June 22, 1945, serial No. 6011.962 In Sweden June 9, 1944 (Cl. Zim-98) 2 Claims.

The present invention has for its object a balance relay of a very simple and effective construction. According to the invention the relay consists of two stationary parallel electro-magnets arranged at some distance from each other and provided with pole pieces, extending perpendlcularly to the axial direction of the magnets. The fields of the magnets are each closed through U-forrned armatures, which are attached to a balance arm, the legs of the said armatures extending along and moving practically parallel to the pole pieces of the electro-magnets. The two armatures are suitably made of a single piece of sheet iron, thus forming an U-shaped trough, which is pivoted at its centre. In order to make possible an adjustment of the air gap between the legs of the armatures and the pole pieces of the electro-magnets, the bottom or web of the U-shaped trough may be cut away at the ends, so that the legs can easily be bent against the pole pieces for adjustment of the air gap between them and the armature. According to the invention the contact member of the relay is suitably formed as a leaf spring, which is clamped in one end and at the other end engages between the prongs of a fork-shaped member extending from the centre of the balance arm, so that this contact member also will give the relay its directional force. This leaf spring is, near the free end, provided with contacts, which make contact with stationary contacts arranged on both sides of the spring.

On the accompanying drawing one form oi the invention is shown by three views perpendicular to each other. Fig. 1 is a side view of the relay, Fig. 2 is a plan view, and. Fig. 3 is an end view of the same.v On the drawing I designates a plate of insulating material, serving as support for the different parts oi.' the relay. On this plate I the electro-magnets 2 are attached by means of two bridges 31 of a nonmagnetic material, for instance brass, said bridges being attached to the plate I by means of screws 5.

The two varmatures embracing the pole pieces 4 extending from the electromagnets 2 consist of, the ends of an U-shaped trough 6 of sheet iron, which is pivoted on the bridges 3l by means of a pivot 1. At the ends of this U-shaped trough the bottom' web portions are cut away, so that only the legs 8 remain and at the mid portion of the U-shaped trough 6 there is a fork-shaped projection 9. between the prongs of which engages the free end o! a leaf spring II attached 2 by the screw I0 to the plate I. On the leaf spring I I, near its free end, contacts I2 are attached, and when the spring is bent to either side, one or other of the contacts I2 is brought in corresponding contact with the contact screw I3.

I claim as my invention:

1. A balance relay comprising two parallel electromagnets, pole pieces at both ends of said electromagnets extending perpendicularly to the longitudinal axis of said electromagnets, pivotally mounted U-shaped armatures embracing said electromagnets and completing their magnetic circuits, a balance arm extending perpendicularly from the armatures and having a forkshaped end, legs at the outer ends of said armatures substantially parallel to the pole pieces and being at the other ends joined by said balance arm, and a leaf spring clamped at one end and supporting the movable contacts of the relay, the other end of said spring being engageable by said fork-shaped end of the balance arm, thus giving the relay its directional force.

2. A balance relay comprising two parallel electromagnets, pole pieces at both ends of said electromagnets extending perpendicularly to the longitudinal axis of said electromagnets, a pivotally mounted armature extending substantially parallel to the pole pieces, a balance arm extending from the mid-portion oi' said armature and having a fork-shaped end, and a leaf spring supporting the movable contacts of the relay and adapted to give the relay its directional force,

the armature and the said balance arm being integral with each other and made of sheet iron bent to U-shape, and the cross-pieces at the ends in front of the electromagnets being cut away to facilitate the adjustment of the air gap.

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REFERENCES CITED The following references are of record in the me of this patent:

UNITED STATES PATENTS Number 

